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  • Open Access

Analysis of discrete modern Hopfield networks in open quantum system

Takeshi Kimura* and Kohtaro Kato†

  • Department of Mathematical Informatics, Graduate School of Informatics, Nagoya University, Nagoya 464-0814, Japan

  • *Contact author: tkimura@nagoya-u.jp
  • †Contact author: kokato@i.nagoya-u.ac.jp
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Phys. Rev. Research 7, 033159 – Published 14 August, 2025

DOI: https://doi.org/10.1103/3966-8xs2

Abstract

The modern Hopfield network, proposed by Krotov and Hopfield, is a mathematical generalization of the Hopfield network, which is a basic model of associative memory that employs higher-order interactions. This study introduces an open quantum model for discrete modern Hopfield networks that generalizes the open quantum Hopfield network. Our model integrates dissipative quantum spin systems, governed by quantum master equations, with classical hopping terms and additional quantum effects through a transverse field. We analytically examined the behavior of the stable fixed points and numerically determined the phase diagram. The results demonstrated qualitatively distinct behaviors from the open quantum Hopfield network, showing that the ferromagnetic and limit cycle phases have additional stable fixed points.

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Phys. Rev. Research 7, 033159– Published 14 August, 2025
  • Received 22 November 2024
  • Accepted 20 June 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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